You clicked the Sign Off link found near the top of the page. Typically, a "Signed off successfully" message will appear at the top of the screen to confirm a proper sign off.
You have done NOTHING for the last XX minutes (usually, 20 minutes) and you were signed off automatically for security reasons. Often, a "signout by timeout" will result in less friendly "You already signed off" or "Session has expired" messages at the top of the screen.
An administrator terminated your session.
No matter how you are signed off the system, you will be returned to the Sign On page. If you attempt to "re- sign on" from this page, you will usually be returned to the page you were viewing before you signed off. Also, with few exceptions, pressing the "BACK" button on your browser will not allow to see MOVEit content unless you sign back on.